臺灣博碩士論文加值系統

本研究設計一單迴圈方形瑞士捲形狀的微形結構，並針對此結構作不同的修改以探討流道之幾何形狀的改變對混合效果的影響。製程中利用SU-8厚膜光阻及微影製程在矽晶圓上製作微混合器之母模，再以液態聚二甲基矽氧烷(polydimethysiloxane，PDMS)翻製微混合器之流道部分及上蓋部分，將兩者接合後即完成實驗所需的微混合器。在實驗上再加上矽膠管與ㄧ個微量式注射幫浦構成系統，使流體能隨著時間被穩定地輸送至微混合器內。此外，本研究利用包含光學顯微鏡、數位攝影機、影像擷取卡及電腦的影像擷取系統將流體在流道中的流動情形拍攝下來。在模擬上本研究使用熱流數值軟體(CFD-ACE+)計算流場狀態，結果顯示:(一) 在高雷諾數下，單迴圈方形瑞士捲混合器的混合效果比T形混合器的好，(二) 就所設計的四種混合器(單迴圈方形瑞士捲、轉角修圓單迴圈方形瑞士捲、內置阻塊單迴圈方形瑞士捲，縮放流道單迴圈方形瑞士捲混合器)中，以縮放流道單迴圈方形瑞士捲混合器的混合效果最佳，且其展開角越大，混合效果越佳，(三) 迴圈數越多，混合器的混合效果越好。

In this work, we design a single-round squared Swiss roll micro structure and a series of variations of the structure to investigate the effects of the changes of geometry of channels on the mixing. In fabrication, the SU-8 thick film photoresist on the silicon wafer is used to fabricate the master mold of micromixer by photolithography and a first patterned PDMS and a top layer one were molded by casting polydimethysiloxane(PDMS) onto the master mold. After bonding both of them, we obtained the experimental micromixer. In experiment, pipes, a micro-syringe pump and the micromixer comprised a system to make the fluid flow being injected into micromixer steadily with time. In addition, an image capture system, including an optical microscope, a CCD camera, an image capture and a personal computer, was used to capture the visualization of the flow field within the channel. We use the commercial codes, CFD-ACE+ to simulate the flow field. The results show that (i) the single-round squared Swiss roll mixer has better mixing performance than the T-shaped one in high Reynolds number, (ii) in four kinds of mixing devices designed with single-round microchannel (single-round squared Swiss roll, rounded-corner single-round squared Swiss roll, obstruction-in-channel single-round squared Swiss roll and shrunk-expanded-channel mixer), the fourth one has the best mixing performance and the larger the expanded angle(θ) is, the better the mixing performance is, (iii) the mixing performance of multi-round version of Swiss roll mixer is better than that of the single-round ones.

目 錄

中文摘要……………………………………………………………….i
英文摘要…………………………………………………………………ii
誌謝………………………………………………………………….. iv
目錄…………………………………………………………………...vi
表目錄………………………………………………………………. .ix
圖目錄……………………………………………………………………x
符號說明…………………………………………………………….xiv

第一章 緒論...........................................1
1-1 研究背景………………………………………………………….1
1-2 文獻回顧………………………………………………………….1
1-3 研究動機……………………………………………………….4
1-4 本文架構………………………………………………………….5
第二章 理論與數值模擬………………………………………………..6
2-1 基本假設………………………………………………………….6
2-2 邊界條件………………………………………………………….7
2-3 統御方程式……………………………………………………….8
2-4無因次分析………………………………………………………..9
2-5 數值模擬……………………………………………………...10
2-5-1前處理……………………………………………………….10
2-5-2模擬計算………………………………………………….10
2-5-3後處理……………………………………………………….11
2-6 混合指標……………………………………………………...11
2-7 微混合器設計………………………………………………...12
2-7-1 A型混合器設計…………………………………………….12
2-7-2 B型混合器設計………………………………………….12
2-7-3 C型混合器設計…………………………………………….12
2-7-4 D型混合器設計…………………………………………….13
第三章 實作及實驗流程.....................................14
3-1 實作流程……………………………………………………...14
3-1-1 光罩設計與製作..................................14
3-1-2 母模製作..................................14
3-1-3以PDMS進行翻模……………………………….18
3-1-4 PDMS接合與管線接合……………………….19
3-2 實驗流程………………………………………...19
3-2-1 微量式注射幫浦與工作流體介紹……………………..19
3-2-2 微混合器之測試………………………………………...19
3-2-3 影像擷取………………………………………………...20
第四章 結果與討論……………………………………………………21
4-1 網格測試......................................21
4-2 實驗與模擬結果之比較……………………...22
4-3高雷諾數改變之影響--混合機制的探討與物理現象的觀察...............................................22
4-4 微結構改變之影響………………………………………...25
4-4-1 轉角為圓角之影響………………………………………..25
4-4-2 阻塊有無之影響………………………………….……..25
4-4-3 展開角( )大小之影響………………………………….26
4-5 迴圈數之影響……………………………………………...28
4-6 壓降之比較…………………………………………………...28
4-7 微混合器之比較…………………………………………...29
第五章 結論與展望...................................31
5-1 結論…………………………………………...31
5-2 展望………………………………………………...32
參考文獻…………………………………………………..33

表目錄
表 4.1 單迴圈A型混合器之網格數比對表………………...36

圖目錄
圖1.1 微混合器示意圖.................................37
圖2.1 微混合器之區域簡介圖…………………………..38
圖2.2 B型與D型混合器的格點分佈設定圖………………………39
圖2.3 A型混合器示意圖.................................40
圖2.4 單迴圈方形瑞士捲混合器之微結構區放大圖…………………41
圖2.5 D型混合器之設計示意圖..........................42
圖3.1 微混合器之製作流程圖…………………………..43
圖3.2 微混合器之母模……………………………………………44
圖3.3 微混合器圖形之光罩………………………………44
圖3.4 聚二甲基矽氧烷(PDMS)之分子式………………………………45
圖3.5 水平調整平台……………………………………..45
圖3.6 母模製造流程圖................................46
圖3.7 固化後的PDMS……………………………………47
圖3.8 氧電漿處理接合後之PDMS………………………………47
圖3.9 矽膠管與PDMS接合後之實體圖…………………………………48
圖3.10 微量式注射幫浦……………………………………………….48
圖3.11 影像擷取系統…………………………………………………49
圖3.12 微混合器母模之流道結構放大圖...................50
圖3.13 微混合器之流道結構放大圖...........................50
圖4.1 不同雷諾數下的單迴圈A型混合器之實驗與模擬濃度分佈..51
圖4.2 體積流率為487.5780 (位於座標原點之Re為70)的B型混合器之實驗與模擬之濃度分佈圖……………………………….52
圖4.3 體積流率為487.5780 (位於座標原點之Re為70)的C型混合器之實驗與模擬之濃度分佈圖………………………………………….53
圖4.4 體積流率為487.5780 (位於座標原點之Re為70)的D型混合器之實驗與模擬之濃度分佈圖…………………………………………….54
圖4.5 雙迴圈方形瑞士捲混合器之實驗與模擬之濃度分佈圖……..55
圖 4.6 三迴圈方形瑞士捲混合器之實驗與模擬之濃度分佈圖…..56
圖4.7 單迴圈方形瑞士捲混合器在不同雷諾數下，於第一個轉角後的xz截面上的濃度分佈圖................................57
圖4.8 單迴圈方形瑞士捲混合器於第一個轉角後的xz截面上的速度向量分佈圖………………………………...58
圖4.9 流體行經路線示意圖.................................59
圖4.10 單迴圈的A型混合器之部分流體粒子之徑線圖..........60
圖4.11 單迴圈的A型混合器之xy截面模擬濃度分佈圖…………..61
圖4.12 單迴圈的A型混合器之xy截面模擬濃度分佈圖……………..62
圖4.13 單迴圈的A型混合器之xy截面模擬濃度分佈圖……………..63圖4.14 單迴圈的A型混合器於xy截面、z = 65 ，第一個轉角之速度向量分佈圖…………………………………………………………64
圖4.15 相同流道寬度與深度(130 130 )的單迴圈方形瑞士捲混合器[(a)~(e)]與T形混合器[(f)~(j)]之流道縱截面(xz或yz)的濃度分佈模擬圖………………..65
圖4.16 單迴圈方形瑞士捲混合器與T形混合器之模擬濃度分佈圖..66
圖4.17 B型混合器之部分xy截面模擬濃度分佈圖…………………..67
圖4.18 A(單迴圈)、B、C，D( = 17.10°)型混合器於接近出口處(距微結構約20倍流道寬度處)的混合指數比較圖……………………..68
圖4.19 流體行經第三個轉角後、於xy截面，z = 65 的速度向量分佈圖...........69
圖4.20 D型混合器之部分流體粒子之徑線圖……………………..70
圖4.21 展開角為17.10ﾟ之D型混合器在流體行經第三個轉角後在xy截面上的速度向量分佈圖……………………………………………..71
圖4.22 D型混合器在流體行經第三個轉角後在xy截面上、z = 65 之速度向量分佈圖……………………………………..72
圖4.23 = 17.10ﾟ之D型混合器於x = 335.7 、y = - 195 至- 325 及z = 0至130 的截面上的速度向量分佈圖………………………...73
圖4.24 不同展開角( )下D型混合器於接近出口處(距微結構約20倍流道寬度處)的混合指數比較圖………………………………………..74
圖4.25 不同迴圈數之A型混合器於接近出口處(距微結構約20倍流道寬度處)的混合指數比較圖…………………………………………75
圖4.26 A(單迴圈)、B、C，D( = 17.10°)型混合器的壓降比較圖…………………76
圖4.27 不同展開角( )下D型混合器的壓降比較圖……………...77
圖4.28 不同迴圈數之A型混合器的壓降比較圖……..............78
圖4.29 不同迴圈數之D型混合器( = 17.10°)於接近出口處(距微結構約20倍流道寬度處)的混合指數比較圖………………….79
圖4.30 體積流率為487.5780 (位於座標原點之Re為70)、各種微混合器於距微結構出口19.9999倍流道寬度之yz截面濃度分佈模擬圖….80
圖5.1 根據結果與討論(第四章)所構想之新型微混合器之示意圖..81

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